If merits of Christ are infinite, then we cannot do anything, need not
do anything.
This forgets the syn Christo theme of St. Paul e.g, Rom 8:17:"We are
heirs together with Christ, provided we suffer with Him so we may be
glorified with Him". cf. also Romans 6:3-8; Col 3:1-3; Eph 2:5-9; Rom
8:9. We get in on the claim He established insofar as we are members of
Him and like Him.